Water-soluble inorganic zinc-rich paint and preparation method thereof

The invention provides a water-soluble inorganic zinc-rich paint and a preparation method thereof. The preparation method comprises the following steps: dropwise adding aluminum-modified silica sol into potassium silicate solution with low modulus, so as to obtain a high-modulus potassium silicate solution as a binder; and adding a catalyst, a siloxane oligomer and a modifier to ensure that the high-modulus potassium silicate solution are uniform in size distribution, and does not have gelatinization reaction for a long time, wherein after the high-modulus potassium silicate solution and a zinc powder mixture are stirred uniformly, the zinc-rich paint has the advantages that reaction rates of all parts of a coating are uniform, and no stress concentration phenomenon exist. Proved by experiments, the zinc-rich paint provided by the invention has no gel after being stored for 90 days at 50 DEG C, the thickness of a film formed once can reach 200 mu m, no cracking or bubbling phenomenon exists, construction can be carried out after the treatment level of the steel surface reaches Sa2, and the salt fog resistance of the coating can reach 10000 hours.